DESCRIPTION: Funds are requested to cover part of the purchase cost of a Cytomation MoFlo High Speed Cell Sorter. The instrument will be installed in the Flow Cytometry Facility of the Cancer Research Laboratory (CRL). The CRL will cover the remainder of the cost of the instrument and the cost of installation from non-federal sources and will provide administrative support for the instrument. The salary of a Staff Research Associated to operate the instrument will be covered by State funds administered by the CRL. Operating costs of the instrument will be borne by pro rata recharges to users. The CRL facility is the only flow cytometry facility on the U.C. Berkeley campus, and currently has a Coulter Elite sorter and three Coulter XL analytical sorters. The Facility is currently used by 42 laboratories, 25 of which use only the analyzers. Of the 17 laboratories that use the sorter, 5 major users account for 80 percent of the use. In the past year demand for sorter time has begun to regularly exceed capacity of our Elite sorter. The high-speed sorter will allow us to meet demand for sorting time. In addition, the instrument will allow us to use new techniques that are not possible on our current instrument, including 4 way sorting, analysis and sorting on more parameters, and experiments involving fluorescence resonance energy transfer.